Oral sodium supplementation on growth and hypertension in preterm infants: an observational cohort study

Area of Science:

• Neonatal physiology and nutrition
• Pediatric nephrology and cardiology

Background:

• Preterm infants often experience suboptimal growth and electrolyte imbalances.
• Enteral sodium supplementation is a common practice, but its impact on growth and hypertension risk requires further investigation.

Purpose of the Study:

• To evaluate the association between enteral sodium supplementation and growth parameters in preterm infants.
• To assess the relationship between enteral sodium supplementation and the development of hypertension (HTN) in this vulnerable population.

Main Methods:

• Retrospective cohort study including 821 preterm infants (22-32 weeks gestation, 450-1500g birth weight).
• Data on enteral sodium supplementation, systolic blood pressure (SBP), weight gain, and potential confounding factors were extracted.
• Statistical analysis, including adjusted odds ratios (OR_ADJ), was used to determine associations.

Main Results:

• Infants receiving sodium supplementation were smaller and less mature.
• Sodium supplementation improved serum sodium levels, weight gain, and head circumference growth without causing hypernatremia.
• No significant correlation was found between urine and serum sodium or urine sodium and weight gain.
• While infants receiving sodium had higher average SBP and HTN rates, supplementation did not increase the odds of hypertension (OR_ADJ 1.02; 0.64-1.64).
• Postnatal steroid use was associated with an increased risk of HTN.

Conclusions:

• Enteral sodium supplementation can safely enhance growth in preterm infants with poor weight gain.
• This supplementation strategy does not appear to increase the risk of hypertension or hypernatremia.
• Postnatal steroid use is a significant risk factor for hypertension in preterm infants.